Dental drill



July 21, 1970 w. H. HARRIS DENTAL DRILL Filed June l0, 1968 UnitedStates Patent O 3,521,359 DENTAL DRILL William H. Harris, 4513 S.Pennsylvania, Oklahoma City, Okla. 73119 Filed June 10, 1968, Ser. No.735,908 Int. Cl. A61c 1 08 U.S. Cl. 32-28 9 Claims ABSTRACT THEDISCLOSURE A dental drill having a head, a drill bit detachably securedin the head, and a handle extending from the head and detachably securedto a plurality of liuid conduits used to convey water and air to thedrill. At least one of the uid conduits is connected to the handlethrough a swivel connection which prevents torque forces from beingimparted to the swivelly connected liuid conduit as the handle istwisted about its longitudinal axis by the manipulations of the dentistin drilling.

BACKGROUND OF THE INVENTION Field of the invention This inventionrelates to dental instruments, and more particularly, to dental drillsof the type having one or more uid conduit lines connected to the handleof the drill.

Brief description of the prior art Dental drills now in use aretypically provided with one, or more frequently, two iiuid conduitsconnected to the handle of the drill for supplying air, and usuallywater, to the head of the drill through tubes which extend through thelength of the handle. The fluid conduits are usually rigidly connectedto the handle of the drill, and thus turn with the handle as it ismanipulated during drilling. In instances where the dentist wishes tochange the angle of drilling this is frequently accomplished by rotatingthe handle of the drill by a wrist action of the dentist. This rotationof the drill handle about its longitudinal axis results in a rotative ortorque force being transmitted to the uid conduits attached to thehandle, and they become twisted. Since they are conventionally made of aresilient material, this twisting is resiliently opposed by theconduits, and when they are in the twisted state, restorative forces ofplastic deformation act constantly to return the conduits to theirrelaxed, untwisted state. The result is that the wrist of the dentistbecomes fatigued over extended periods of drilling, and considerablediscomfort is experienced by the dentist. Moreover, the eiiiciency andproficiency of the drilling operation being performed may bedetrimentally atfected by such fatigue.

BRIEF DESCRIPTION OF THE PRESENT INVENTION The present inventionprovides an improved dental drill which enables the dentist to moreeasily drill over extended periods of time without sustaining fatiguewhich impairs eliciency and accuracy. Broadly described, the drillcomprises a drill handle secured at one end to a drill head whichcarries a drill bit, and having at least one uid conduit secured to theopposite end of the drill handle through a swivel connection whichpermits the drill handle to be turned or rotated about its axis withouta torque force being imparted to the uid conduit. More specifically,though Without limitation being intended, the invention comprises exibleair and water conduits connected to the drill shank or handle, with atleast one of these conduits being connected to the handle through aswivel collar which swivelly engages a swivel sleeve which 3,521,359Patented July 21, 1970 ICC is, in turn, connected to an insert blockwhich is sealingly and detachably connectable to the drill handle. Theconnection of the insert block to the drill handle is achieved by theuse of an internally threaded collar which threads onto an externallythreaded end portion of the drill handle.

The described drill structure permits several important objects of theinvention to be achieved, including:

(a) making the drill easier to manipulate by the dentist;

(b) increasing the effective service life of the fluid conduits used toconvey liuid to the drill; and

(c) reducing wrist and arm fatigue experienced by the dentist during theuse of the drill.

In addition to those objects and advantages already described,additional objects and advantages will become apparent as the followingdetailed description of the invention is read in conjunction with theaccompanying drawings which illustrate the invention.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view in elevation of adental drill constructed in accordance with the present invention.

FIG. 2 is a view of a portion of the dental drill shown in FIG. lillustrating certain structural elements in section, and certain partsin elevation.

FIG. 3 is a sectional View taken along line 3--3 of FIG. 2.

FIG. 4 is a sectional view taken along line 4-4 of FIG. 3.

FIG. 5 is a sectional view taken along line 5-5 of PIG. 2.

DETAILED DESCRIPTION OF A PREFERRED' EMBODIMENT OF THE INVENTIONReferring initially to FIG. l of the drawing, shown therein is a dentaldrill constructed in accordance with a preferred embodiment of theinvention, and designated generally by reference numeral 10. The drill10 includes a head 12 which contains a chuck or collet which receivesthe drill bit 14. The drill 10 further includes a handle or shankportion 16 which threadedly engages a collar 18, which functions in amanner hereinafter described to secure to the drill shank 16, an airconduit 20 and a water conduit 22.

One of the salient features of the invention is the manner in which oneor both of the air and water conduits 20 and 22 are connected to thedrill 10 through a swivel connection which permits the drill to be moreeasily and ef fectively utilized by the dentist, particularly withrespect to a reduction in the fatigue which is experienced by thedentist over a prolonged period of drilling. To impart a betterunderstanding of the manner in which the swivel coupling or connectionforming a part of the invention is constructed, it will be helpful toinitially describe certain aspects of conventional or typical dentaldrill construction.

As is generally well known, most dental drills are air driven and, tothis end, an air tube 24 is extended through the hollow handle 16 of thedrill 10 for the purpose of supplying the air necessary to drive thedrill bit 14 in rotation. It is also typical construction in dentaldrills of this type to supply water to the surface being drilled inorder to cool this surface and wash away debris resulting from thedrilling. In the drill 10 illustrated in the drawings, a water tube 26is provided for conveying water to a small jet (not seen) located in thehead 12 of the drill. It will be noted in referring to FIG. 2 that thehandle or shank 16 of the drill 10 is externally threaded at its end 27which is threadedly connected to the collar 18, and that, within thisexternally threaded portion of the handle, the air tube 24 and watertube 26 which extend through the handle project to terminal or endportions which are spaced axially inwardly from the end of theexternally threaded portion 27 of the handle 16.

In further description of the typical or conventional dental drillconstruction, there is provided a conduit connector fitting which isdesignated generally by reference numeral 30 in the drawings. Theconduit connector fittnig 30 includes an insert block 32 ofsubstantially cylindrical cross-sectional configuration, which insertblock is dimensioned to fit within the externally threaded end portion27 of the handle 16 of the drill with sufficient clearance between thisportion of the handle and its exterior surface to accommodate in thisspace a compression cap 34. It will be noted in referring to FIG. 2 thatthe insert body 32 is provided with an annular flange 36 which extendsaround the outer periphery thereof, and with a protuberant, generallyaxially extending, air conduit nipple 38 and a protuberant water conduitnipple 40.

Formed in the end of the insert block 32 which is positioned within theexternally threaded end portion 27 of the handle 16 is an aircounterbore 42 and a water counterbore 44. These counterbores 42 and 44communicate respectively with an elongated air bore 46 and water bore 48which extend coaxially through the air nipple 38 and water nipple 40,respectively. It will further be noted in referring to FIGS. 3-5 thatthe insert block 32 is provided with diametrically opposed, axiallyextending grooves 50 which are aligned, and communicate, with airexhaust openings 52 formed in the base 54 of the compression cap 34, aswell as with air exhaust passageways 56 which extend through the handle16 of the drill in proximity to the drill head 12. It will also be notedin referring to FIGS. 2 and 5 that the compression cap 34, in additionto being provided with the air exhaust openings 52 in the base 54thereof, is also slotted or grooved in diametrically opposed portions ofits side wall 60. The air exhaust passageways 56 function to convey airexhausted from the drill turbine away from the area of the drilling, andexhaust such air to the atmosphere. In referring to FIGS. 2 and 3, itwill be noted that the axially extending grooves 50 open into the hollowor open interior 58 of the collar 18, so that air is exhausted from theinterior of this collar to the atmosphere.

The compression cap 34 carries an annular, radially outwardly extendingflange 62 and slides over the insert block 32. The cap 34 retains undercompression between its base 54 and the insert block 32, a resilientsealing element 64. The resilient sealing element has a pair ofapertures 66 and 68 formed therethrough for sealingly i accommodatingthe air tube 24 and the water tube 26. The collar 18 is internallythreaded for threaded engagement With the externally threaded endportion 27 of the handle 16, and further includes an annular, radiallyinwardly extending shoulder 70. When the collar 18 is threadedly engagedwith the externally threaded end portion 27 of the handle 16 in themanner depicted in FIG. 2, the shoulder 70 bears against the flange 36of the insert block 32, and forces the insert block inwardly in an axialdirection into the threaded end portion 27 of the handle. Since thecompression cap 34 is prevented from moving in an axial direction withrespect to the handle 16 because of the enga-gement of the flange 62With the threaded end portion 27, the result of the forced inwardmovement of the insert block 32 is to compress the sealing element 64.This effects a tight seal around the air tube 24 and the water tube 26.

Pressed over the protuberant air conduit nipple 38 of the insert block32 is a synthetic resin swivel sleeve 74. The swivel sleeve 74 isretained on the air conduit nipple 38 by a retaining ring 76. At itsouter end, the swivel sleeve 74 is provided with an annular flange 78,which flange is swivelly engaged by a swivel collar 80 having inturnedflanges 82 which hook over and rotatably interlock with the flange 78 onthe swivel sleeve 74 and a if shoulder 83 on a nipple fitting 84. Thenipple fitting 84 is provided with a plurality of serrations or ribs 86which function to frictionally retain the flexible air conduit 20 whichhas one end thereof pressed over the fitting 84. The filing 84 isprovided with an axially extending bore 88 therethrough, which bore isaligned, and in communication, with an axial bore 90 which extendsthrough the swivel sleeve 74 into communication with the bore 46 throughthe nipple 38. The end of the water conduit 22 is frictionally pressedover the water conduit nipple 40.

OPERATION In assembling or disassembling the dental drill of theinvention, disconnection of the handle 16, head 12 and drill bit 14 fromthe fluid supply lines is eflected by unscrewing the collar 18 from theexternally threaded end portion 27 of the handle. When the collar 18 isloosened in this manner, the insert block 32 and the compression cap 34which is pressed thereover, may be easily withdrawn from the externallythreaded end portion 27 of the handle 16. The same procedure, with thesteps carried out in reverse order, is utilized when it is desired toconnect the air conduit 20 and water conduit 22 to the handle or shank16 of the drill 10 preparatory to using it for drilling. When theinternally threaded collar 18 is connected to the externally threadedend portion 27 of the handle 16 in the manner depicted in FIG. l, thedrill is ready for use.

The swivel connection employed in the invention functions to permit thedrill to be rotated about the axis of the shank or handle 16 withoutimparting a twist or torque to the air conduit 20. In other,non-illustrated embodiments, the same may be true of the water conduit22. As the dentist, in using the drill, finds it necessary to change theangle of drilling by canting or angling the bit 14, this is oftenaccomplished by rotating or twisting the wrist. This motion will in turncause the handle 16 to be rotated about its axis. This rotationalmovement is imparted through the insert block 32 to the swivel sleeve74. The annular flange 78 of the swivel sleeve 74 is free to turn,however, in the inturned flange 82 of the swivel collar 80, so that notorque or twisting movement is transmitted to the air conduit 20 Whichis connected to the nipple fitting 84. Thus, the air conduit 20 remainsin its relaxed status and is not loaded in resilient deformation. Thus,there is no force stored in the air conduit which acts to constantlyoppose the wrist action of the dentist in manipulating the drill, so asto make such manipulation more difficult.

Although a preferred embodiment of the invention has been hereindescribed and is illustrated in the drawings, it will be appreciatedthat various changes and innovations can be effected without departurefrom the basic principles which underlie the invention. Changes andinnovations of this type are deemed to be included within the spirit andscope of the invention except as the same may be necessarily excludedfrom the invention by the appended claims or reasonable equivalentsthereof.

What is claimed is:

1. A dental drill comprising:

an elongated drill handle;

a drill head secured to one end of said drill handle;

a drill bit rotatably journaled in said drill head;

at least one fluid conduit for conveying fluid to the drill handle;

a swivel sleeve having a bore therethrough and connected to said drillhandle, said sleeve having an annular flange thereon positionedconcentrically with respect to the bore through said sleeve;

a nipple fitting including a projecting neck portion having a boreextending therethrough, and having an annular shoulder around said neckportion at one end thereof, said neck portion extending into, andfrictionally engaging, said one fluid conduit; and

a swivel collar having a first flange engaging the shoulder of saidnipple fitting, and having a second llange swivelly engaging saidannular llange of said swivel sleeve whereby said sleeve and collar canrotate relative to each other.

2. A dental drill as defined in claim 1 and further characterized toinclude a conduit connector litting connecting the swivel sleeve to thedrill handle, said conduit connector iitting comprising:

an insert 'block having a bore extending therethrough and having a rstportion inserted in said opposite end of the handle;

a ange extending around the outside of said insert block at one end ofsaid lirst portion; and

a nipple concentrically surrounding a portion of the bore in said insertblock and projecting into said swivel sleeve; and

a collar threadedly engaging the exterior of the opposite end of saidhandle and including a shoulder cooperating with the flange of saidinsert block to force said first portion of said insert block into saidopposite end of the handle when said last-mentioned collar is threadedon said handle.

3. A dental drill comprising:

an elongated hollow drill handle;

a drill head secured to one end of said drill handle;

a drill bit rotatably journaled in said drill head;

at least one iluid conduit for conveying a uid to the drill handle;

a swivel connection swivelly connecting at least one of said fluidconduits to the opposite end of said drill handle from said drill headfrom that to which said drill head is rotatably journaled for avoidingtwisting of said swivelly connected conduit when said drill is rotatedabout the longitudinal axis of said drill handle;

fluid tubes extending lengthwise through said hollow drill handle, andincluding end portions extending into the hollow interior of saidopposite end of said drill handle; and

an insert block detachably engaged with said opposite end of said drillhandle and having fluid conveying bores extending therethrough, saidblock having said swivel connections secured thereto for communicationwith said iluid tubes through said fluid conveying bores, and said uidconveying bores of said insert block receiving said lluid tube endportions.

4. A dental drill as defined in claim 3 wherein said insert block isfurther characterized as including:

a ilange extending around at least a portion of the outside thereof andhaving a diameter larger than the inside diameter of the hollow interiorof said opposite end of the handle; and

va collar threadedly engaging the outside of said opposite end of thehandle, and engaging the ange of said insert block to retain said insertblock seated in the hollow interior of said opposite end of the handle.

5. A dental drill as defined in claim 3 and further characterized toinclude a compression cap positioned around a portion of said insertblock and inside said hollow interior of said opposite end of thehandle, said compression cap having a ange extending radially outwardlytherefrom, said ange having a larger diametric dimension than the insidediameter of said hollow interior;

a resilient sealing element positioned between said compression cap andsaid insert block, and surrounding and sealingly engaging said tluidtubes; and

means for moving said insert block toward said sealing element to placesaid sealing element in compression.

6. A dental drill as delined in claim 4 wherein said swivel connectioncomprises:

a swivel sleeve having a bore therethrough and connected to said insertblock for placing the bore there- 6 through in communication with one ofthe iluid conveying bores through said insert block, said swivel sleevehaving an annular flange thereon positioned concentrically with respectto the bore through said sleeve;

a nipple fitting including a projecting neck portion having a boreextending therethrough, and having an annular shoulder around said neckportion at one end thereof, said neck portion extending into, andfrictionally engaging, said one fluid conduit; and

a swivel collar having a first flange engaging the shoulder of saidnipple litting, and having a second ilange swivelly engaging saidannular flange of said swivel sleeve whereby said sleeve and collar canrotate relative to each other.

7. A dental drill as defined in claim 6 and further characterized toinclude:

a compression cap positioned around a portion of said insert block andinside said hollow interior of said opposite end of the handle, saidcompression cap having av ange extending radially outwardly therefrom,said tlange having a larger diametric dimension than the inside diameterof said hollow interior;

a resilient sealing element positioned between said compression cap andsaid insert block, and surrounding and sealingly engaging said fluidtubes; and

means for moving said insert block toward said sealing element to placesaid sealing element in compression.

8. A dental drill comprising:

an elongated drill handle;

a drill head secured to one end of said drill handle;

a drill ybit rotatably journaled in said drill head;

at least one fluid conduit for conveying a fluid to the drill handle;

a swivel connection swivelly connecting at least one of said iluidconduits to the opposite end of said handle from said drill head and foravoiding twisting of said swivelly connected conduit when said drill isrotated about the longitudinal axis of said drill handle;

uid tubes extending lengthwise through said handle;

and

an insert block detachably engaged with said opposite end of said handleand having iluid conveying bores extending therethrough, said blockcomprising:

an air conduit nipple projecting from the opposite side thereof fromsaid handle and into said swivel connection; a water conduit nippleprojecting from the opposite side thereof from said handle; and a Waterconduit connected to said water conduit nipple. 9. A dental drillcomprising: an elongated drill handle; a drill head secured to one endof said drill handle; a drill bit rotatably journaled in said drillhead; at least one uid conduit for conveying iluid to the drill handle;a nipple litting having a bore therethrough and an annular shoulderthereon concentric to said bore; va swivel sleeve having a boretherethrough and connected to said drill body, said sleeve having a angetherearound concentric to the bore therethrough; and

a collar swivelly interconnecting said sleeve and nipple -ftting andplacing the bores of said nipple litting and sleeve in communicationwith each other.

References Cited UNITED STATES PATENTS ROBERT PBsHocK, Primary Examiner

